"On being asked this by those who have gone forth in other sects, this is how you should answer."

(sabbe dhammā). It means the five khandhas, but it also means 'The All' and 'The World' and any other grouping that means 'all things.'

— p.p.

[1] According to the Commentary to AN 8:99 — AN 8:83 in the PTS edition — which covers the first eight of the ten questions given here, "all phenomena" (sabbe dhammā) here means the five aggregates. These are rooted in desire, it says, because the desire to act (and thus create kamma) is what underlies their existence. The Commentary’s interpretation here seems to be an expansion on MN 109, in which the five clinging-aggregates are said to be rooted in desire, an assertion echoed in SN 42:11, which states that suffering & stress are rooted in desire. Here, all the aggregates — whether affected by clinging or not — are said to be rooted in desire.

The Commentary goes on to say that the statement, "All phenomena are rooted in desire," deals exclusively with worldly phenomena, whereas the remaining statements about all phenomena cover both worldly and transcendent phenomena. There seems less reason to follow the Commentary’s first assertion here, in that the noble eightfold path, when brought to maturity, counts as transcendent, and it is obviously rooted in a skillful form of desire mentioned in the factor of right effort.

As for the transcendent in its ultimate form, the phrase "all phenomena" as used in this sutta does not cover unbinding, as unbinding is not rooted in anything and, as the final statement indicates, it constitutes the final end of all phenomena. Thus this sutta would seem to belong to the group of suttas that would not classify unbinding as a phenomenon. (On this question, see the note to AN 3:134 DTO: #137.)

[2] The image here derives from a standard analogy comparing the practice to the act of crossing a river. According to AN 7:15, the point where the meditator gains footing on the river bottom, but before getting up on the bank, corresponds to the attainment of non-return. To become an arahant is to go beyond the river and stand on firm ground.